Department of Pathology

Calculating and Interpreting the Estimated Glomerular Filtration Rate (eGFR)

Glen Mott, Wieslaw Furmaga

The calculation of the eGFR is recommended with each creatinine result reported in outpatients. Links to other sources dealing with CKD and a link to a calculator for the eGFR in pediatric patients (< 18 years of age) and to a calculator for the eGFR in adult patients (>18 <71 years of age) are provided at the bottom of this page .

The GFR is usually accepted as the best index of kidney function. The eGFR, estimated glomerular filtration rate, is calculated by the MDRD equation for an average body weight from the patientŐs age, sex, race (African-American or not), and serum creatinine.  The MDRD equation is used for patients from 18 to 70 years of age with stable BUN and creatinine values (i.e. not changing significantly from day to day) and is calculated separately for non-African Americans and African Americans as the latter have a higher GFR at the same level of serum creatinine.

Normal GFR in young adults is approximately 120-130 ml/min/1.73m2 and declines with age. As a decrease in GFR precedes the onset of renal failure, a persistently low value is a specific indicator of chronic kidney disease (CKD).   Patients with an eGFR from 30-59 have moderate CKD, 15-29 severe CKD, and <15 kidney failure.

The MDRD equation is recommended by the National Kidney Foundation, American Society of Nephrology, and the National Kidney Disease Education Program of the National Institutes of Health.   It was developed from a group of predominantly Caucasian, non-diabetic patients with a mean GFR of 40 ml/min/1.73m2, but it has been validated in diabetic kidney disease, kidney transplant recipients and African-Americans with non-diabetic renal disease. The MDRD equation has not been evaluated in those <18 yrs and > 70yrs of age, during pregnancy, in normal individuals or racial/ethnic subgroups other than Caucasians and African Americans. Therefore, 24 hr urine collections to estimate GFR may be appropriate in individuals not included in groups previously evaluated such as in patients who are elderly or those with skeletal muscle disease, with rapidly changing renal function and in vegetarians.

For more information see the National Kidney Foundation Web Site

Information is available on this site for estimating the GFR if the patient has an extreme body weight (high or low) or for adjusting dosages of drugs that could cause renal toxicity.  Conditions or other diseases that may affect the eGFR are also provided.

If you have questions regarding this information, please contact Dr. Furmaga (567-4115)

We appreciate the assistance of the members of the Divisions of Nephrology in the Departments of Internal Medicine and Pediatrics with preparation of this information.


Calculation for 60 yr old non-African American woman:

Creatinine = 1.5 mg/dL

Estimated glomerular filtration rate (eGFR)  = 38 mL/min/1.73 m2


Chronic Kidney Disease:  eGFR less than 60 mL/min/1.73m2; 

Mean GFR for women, 60-69 yrs of age: 85mL/min/1.73m2

For information regarding disease staging see: National Kidney Foundation: About Chronic Kidney Disease

An eGFR>60mL/min/1.73m2 also may warrant medical follow-up IF accompanied by proteinuria, hematuria or other evidence of renal disease.

For Calculation of the eGFR in Adults >18 <71Years: Click Here

For Calculation of the eGFR in Children <18 Years: Click Here

1. The information in the DOLS web site is developed for and intended to help the clinicians of our academic medical community: The University Health System; The University of Texas Health Science Center at San Antonio; The South Texas Veterans Healthcare System: Audie Murphy Memorial Veterans Hospital.
2. If you are from outside of our community and you find that the information is helpful, you are welcome to it, however, we encourage you to consult with your local experts and your health science center libraries for more information.

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Last updated on 30 October 2006 by John D. Olson, M.D., Ph.D.